immuredanchorite [he/him, any]

if they hadn’t built the city in the middle of an inhospitable landscape they could have just planted some trees

This seems like it was written by someone who hasn’t studied logic enough… There is a distinction between whether an argument is Valid or Sound… Validity has to do with whether the argument is logically consistent, Soundness has to do with whether or not the suppositions are factual or not, I believe after validity is established. You can have a valid argument that is not sound, and you can have an invalid argument in which all of the statements are truthful.